• Year
  • 1922
perfect model
  • Category
  • Radio module pre 1926 (not a part, not a key)
  • Radiomuseum.org ID
  • 228391

Click on the schematic thumbnail to request the schematic as a free document.

 Technical Specifications

  • Number of Tubes
  • 2
  • Valves / Tubes
  • TM TM
  • Main principle
  • Radio Frequency Amplification only; something special ? Please give information (notes)
  • Power type and voltage
  • Storage and/or dry batteries / 4 & 80 Volt
  • Loudspeaker
  • - For headphones or amp.
  • Material
  • Wooden case
  • from Radiomuseum.org
  • Model: Radio-Puzzle RPD - SBR Société Belge Radio-
  • Shape
  • Tablemodel, Box - most often with Lid (NOT slant panel).
  • Dimensions (WHD)
  • 190 x 190 x 200 mm / 7.5 x 7.5 x 7.9 inch
  • Notes
    • This unit is part of the so-called "Radio-Puzzle" which is modular in conception by placing every stage in a different module. It could be configured not only as a radio with different principles but also as telegraphy receiver and writer or as measuring equipment.
    • By combination of different units, one gets a complete radio or other application.
    • All connections are made with wires in clamping screws.
    • The clamping screws for the filament "A" battery and the plate voltage "B" battery are placed at the same height/depth so that they can be easily interconnected. The whole powerline setup is made as a daisy chain.
    • These units were initially manufactured and commercialised by S.I.B. from 1920 on before SBR took over the retailing under their own label in 1922.
    • Used coils on these units are Disco-self 1922 or the preceding SIB Disco-Self 1920. They are optionally mounted on the side panels of units A, B and E. The obtainable frequency range with those coils was approximately 13kHz (23000m) to 1,75MHz (170m).
    • The following modules of the Radio-Puzzle are known:
      • RPA = Tuning module and optionally a crystal detector. Despite the fact that this unit doesn't need power, it has power connectors to pass along the current to the next unit;
      • RPB = Tuning module with RF amplifier and detector;
      • RPC = RF amplifier with regenerative feedback or an autodyne with a "Compensateur"1 and optionally a detector;
      • RPD = RF amplifer with RC2 interstage coupling (autodyne amplifier together with RPC). However, this unit can be used as LF amplifier stage also;
      • RPE = LF amplifier with interstage transformers;
      • RPF = Tube detector (not an amplifier) to drive a morse writer or a repeater morse key. Driving power for the following relais after this unit comes from the preceding LF amplifier module (see schematic and explanation at the bottom of this page);
      • RPG = Variable coupling unit for 2 disco-self coils from which 1 has fixed position on the preceding unit RPA, RPB;
      • RPR = Variable coupling unit for 3 disco-self coils from which 1 has fixed position. It could be used to make a regenerative circuit by variable induction.

    Alternative for TM tubes: Marconi_R

    1 Compensateur: the differential variable capacitor to control the positive and negative feedback. Not a butterfly capacitor.
    2 Resistor and capacitor.

  • Price in first year of sale
  • 242.00 BFr
  • Author
  • Model page created by Dirk Bladt. See "Data change" for further contributors.

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